compositeelresolver.html

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<CODE>&nbsp;boolean</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../javax/el/CompositeELResolver.html#isReadOnly(javax.el.ELContext, java.lang.Object, java.lang.Object)">isReadOnly</A></B>(<A HREF="../../javax/el/ELContext.html" title="class in javax.el">ELContext</A>&nbsp;context,
           <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;base,
           <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;property)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;For a given <code>base</code> and <code>property</code>, attempts to
 determine whether a call to <A HREF="../../javax/el/CompositeELResolver.html#setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)"><CODE>setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)</CODE></A> will always fail.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../javax/el/CompositeELResolver.html#setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)">setValue</A></B>(<A HREF="../../javax/el/ELContext.html" title="class in javax.el">ELContext</A>&nbsp;context,
         <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;base,
         <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;property,
         <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;val)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Attempts to set the value of the given <code>property</code> 
 object on the given <code>base</code> object.</TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TH ALIGN="left"><B>Methods inherited from class java.lang.<A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A></B></TH>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#clone()" title="class or interface in java.lang">clone</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#equals(java.lang.Object)" title="class or interface in java.lang">equals</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#finalize()" title="class or interface in java.lang">finalize</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#getClass()" title="class or interface in java.lang">getClass</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#hashCode()" title="class or interface in java.lang">hashCode</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#notify()" title="class or interface in java.lang">notify</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#notifyAll()" title="class or interface in java.lang">notifyAll</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#toString()" title="class or interface in java.lang">toString</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#wait()" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#wait(long)" title="class or interface in java.lang">wait</A>, <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html#wait(long, int)" title="class or interface in java.lang">wait</A></CODE></TD>
</TR>
</TABLE>
&nbsp;
<P>

<!-- ========= CONSTRUCTOR DETAIL ======== -->

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<B>Constructor Detail</B></FONT></TH>
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<A NAME="CompositeELResolver()"><!-- --></A><H3>
CompositeELResolver</H3>
<PRE>
public <B>CompositeELResolver</B>()</PRE>
<DL>
</DL>

<!-- ============ METHOD DETAIL ========== -->

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<B>Method Detail</B></FONT></TH>
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<A NAME="add(javax.el.ELResolver)"><!-- --></A><H3>
add</H3>
<PRE>
public void <B>add</B>(<A HREF="../../javax/el/ELResolver.html" title="class in javax.el">ELResolver</A>&nbsp;elResolver)</PRE>
<DL>
<DD>Adds the given resolver to the list of component resolvers.

 <p>Resolvers are consulted in the order in which they are added.</p>
<P>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>elResolver</CODE> - The component resolver to add.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/NullPointerException.html" title="class or interface in java.lang">NullPointerException</A></CODE> - If the provided resolver is
     <code>null</code>.</DL>
</DD>
</DL>
<HR>

<A NAME="getValue(javax.el.ELContext, java.lang.Object, java.lang.Object)"><!-- --></A><H3>
getValue</H3>
<PRE>
public <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A> <B>getValue</B>(<A HREF="../../javax/el/ELContext.html" title="class in javax.el">ELContext</A>&nbsp;context,
                       <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;base,
                       <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;property)</PRE>
<DL>
<DD>Attempts to resolve the given <code>property</code> object on the given
 <code>base</code> object by querying all component resolvers.

 <p>If this resolver handles the given (base, property) pair, 
 the <code>propertyResolved</code> property of the 
 <code>ELContext</code> object must be set to <code>true</code>
 by the resolver, before returning. If this property is not 
 <code>true</code> after this method is called, the caller should ignore 
 the return value.</p>

 <p>First, <code>propertyResolved</code> is set to <code>false</code> on
 the provided <code>ELContext</code>.</p>

 <p>Next, for each component resolver in this composite:
 <ol>
   <li>The <code>getValue()</code> method is called, passing in
       the provided <code>context</code>, <code>base</code> and 
       <code>property</code>.</li>
   <li>If the <code>ELContext</code>'s <code>propertyResolved</code>
       flag is <code>false</code> then iteration continues.</li>
   <li>Otherwise, iteration stops and no more component resolvers are
       considered. The value returned by <code>getValue()</code> is
       returned by this method.</li>
 </ol></p>

 <p>If none of the component resolvers were able to perform this
 operation, the value <code>null</code> is returned and the
 <code>propertyResolved</code> flag remains set to 
 <code>false</code></p>.

 <p>Any exception thrown by component resolvers during the iteration
 is propagated to the caller of this method.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../javax/el/ELResolver.html#getValue(javax.el.ELContext, java.lang.Object, java.lang.Object)">getValue</A></CODE> in class <CODE><A HREF="../../javax/el/ELResolver.html" title="class in javax.el">ELResolver</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>context</CODE> - The context of this evaluation.<DD><CODE>base</CODE> - The base object whose property value is to be returned,
     or <code>null</code> to resolve a top-level variable.<DD><CODE>property</CODE> - The property or variable to be resolved.
<DT><B>Returns:</B><DD>If the <code>propertyResolved</code> property of 
     <code>ELContext</code> was set to <code>true</code>, then
     the result of the variable or property resolution; otherwise
     undefined.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/NullPointerException.html" title="class or interface in java.lang">NullPointerException</A></CODE> - if context is <code>null</code>
<DD><CODE><A HREF="../../javax/el/PropertyNotFoundException.html" title="class in javax.el">PropertyNotFoundException</A></CODE> - if the given (base, property) pair
     is handled by this <code>ELResolver</code> but the specified
     variable or property does not exist or is not readable.
<DD><CODE><A HREF="../../javax/el/ELException.html" title="class in javax.el">ELException</A></CODE> - if an exception was thrown while performing
     the property or variable resolution. The thrown exception
     must be included as the cause property of this exception, if
     available.</DL>
</DD>
</DL>
<HR>

<A NAME="getType(javax.el.ELContext, java.lang.Object, java.lang.Object)"><!-- --></A><H3>
getType</H3>
<PRE>
public <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Class.html" title="class or interface in java.lang">Class</A>&lt;?&gt; <B>getType</B>(<A HREF="../../javax/el/ELContext.html" title="class in javax.el">ELContext</A>&nbsp;context,
                        <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;base,
                        <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;property)</PRE>
<DL>
<DD>For a given <code>base</code> and <code>property</code>, attempts to
 identify the most general type that is acceptable for an object to be 
 passed as the <code>value</code> parameter in a future call 
 to the <A HREF="../../javax/el/CompositeELResolver.html#setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)"><CODE>setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)</CODE></A> method. The result is obtained by 
 querying all component resolvers.

 <p>If this resolver handles the given (base, property) pair, 
 the <code>propertyResolved</code> property of the 
 <code>ELContext</code> object must be set to <code>true</code>
 by the resolver, before returning. If this property is not 
 <code>true</code> after this method is called, the caller should ignore 
 the return value.</p>

 <p>First, <code>propertyResolved</code> is set to <code>false</code> on
 the provided <code>ELContext</code>.</p>

 <p>Next, for each component resolver in this composite:
 <ol>
   <li>The <code>getType()</code> method is called, passing in
       the provided <code>context</code>, <code>base</code> and 
       <code>property</code>.</li>
   <li>If the <code>ELContext</code>'s <code>propertyResolved</code>
       flag is <code>false</code> then iteration continues.</li>
   <li>Otherwise, iteration stops and no more component resolvers are
       considered. The value returned by <code>getType()</code> is
       returned by this method.</li>
 </ol></p>

 <p>If none of the component resolvers were able to perform this
 operation, the value <code>null</code> is returned and the
 <code>propertyResolved</code> flag remains set to 
 <code>false</code></p>.

 <p>Any exception thrown by component resolvers during the iteration
 is propagated to the caller of this method.</p>
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../javax/el/ELResolver.html#getType(javax.el.ELContext, java.lang.Object, java.lang.Object)">getType</A></CODE> in class <CODE><A HREF="../../javax/el/ELResolver.html" title="class in javax.el">ELResolver</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>context</CODE> - The context of this evaluation.<DD><CODE>base</CODE> - The base object whose property value is to be analyzed,
     or <code>null</code> to analyze a top-level variable.<DD><CODE>property</CODE> - The property or variable to return the acceptable 
     type for.
<DT><B>Returns:</B><DD>If the <code>propertyResolved</code> property of 
     <code>ELContext</code> was set to <code>true</code>, then
     the most general acceptable type; otherwise undefined.
<DT><B>Throws:</B>
<DD><CODE><A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/NullPointerException.html" title="class or interface in java.lang">NullPointerException</A></CODE> - if context is <code>null</code>
<DD><CODE><A HREF="../../javax/el/PropertyNotFoundException.html" title="class in javax.el">PropertyNotFoundException</A></CODE> - if the given (base, property) pair
     is handled by this <code>ELResolver</code> but the specified
     variable or property does not exist or is not readable.
<DD><CODE><A HREF="../../javax/el/ELException.html" title="class in javax.el">ELException</A></CODE> - if an exception was thrown while performing
     the property or variable resolution. The thrown exception
     must be included as the cause property of this exception, if
     available.</DL>
</DD>
</DL>
<HR>

<A NAME="setValue(javax.el.ELContext, java.lang.Object, java.lang.Object, java.lang.Object)"><!-- --></A><H3>
setValue</H3>
<PRE>
public void <B>setValue</B>(<A HREF="../../javax/el/ELContext.html" title="class in javax.el">ELContext</A>&nbsp;context,
                     <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;base,
                     <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;property,
                     <A HREF="http://java.sun.com/j2se/1.5/docs/api/java/lang/Object.html" title="class or interface in java.lang">Object</A>&nbsp;val)</PRE>
<DL>
<DD>Attempts to set the value of the given <code>property</code> 
 object on the given <code>base</code> object. All component
 resolvers are asked to attempt to set the value.

 <p>If this resolver handles the given (base, property) pair, 
 the <code>propertyResolved</code> property of the 
 <code>ELContext</code> object must be set to <code>true</code>
 by the resolver, before returning. If this property is not 
 <code>true</code> after this method is called, the caller can
 safely assume no value has been set.</p>

 <p>First, <code>propertyResolved</code> is set to <code>false</code> on
 the provided <code>ELContext</code>.</p>

 <p>Next, for each component resolver in this composite:
 <ol>
   <li>The <code>setValue()</code> method is called, passing in